I've used a number of GPS receivers on the train as follows:
Garmin GPS III+ (the old workhorse) -
Pros
- the flip up quad helix antenna works pretty well at bringing in signals - once it is synced
- can store about 5000 data points, which seems to be more than sufficient to cover most LD overnight trips
- can attach external antenna for better reception
- provides serial data that can be used with a number of mapping applications in real time
- serial connection also allows data to be transferred to PC trip
Cons
- older technology, may not sync while train is in motion
- not the smallest GPS receiver in the world
- about 12-17 hours of battery life, but can use 12 VDC w/converter for external power
- only records 2D position (which may not be a problem if you are not interested in elevation)
Garmin e-Trex (another old work horse)
Pros
- reasonable signal reception if placed against the window (I made a small suction cup mount to attach e-Trex to window - works well)
- can store data points (more than 5000, depending upon model) - usually more than sufficient for most LD runs
- provides serial data that can be used with a number of mapping application in real time
- serial connection also allows data to be transferred to PC after trip
Cons
- e-Trex is meant for hiking - not necessarily for train
- no signal reception unless placed against the window
- about 17+/- hours of battery life, but can use 12 VDC w/converter for external power
Garmin Nuvi
Pros
- great signal reception
- great logging features
- nice map
- great window mount
Cons
- may need 12 VDC converter or AC "wall wart" to power the unit
DeLorme Earthmate USB (w/Street Atlas application)
Pros
- excellent signal reception once synced (recommend synching at station before boarding train)
- small, light weight - great option if you are bringing and using your laptop on the train
- no battery or power limitations since it feeds off your PC
Cons
- the little suction cup window mount that comes with the package is not the greatest
- data stored in DeLorme GPS native format (not a big problem - but need to convert to view in other map applications)
Reading the other posts - I am interested in learning more about how folks capture GPS data on their smart phones and transfer to PC. I recently purchased Droid 2 (like 2 weeks ago) and am still negotiating learning curve. I'd like to learn how to access GPS data and transfer to PC - would appreciate some pointers.
Also for consideration - would it make sense to make a dedicated thread for GPS? It seems like we respond to questions about what GPS receivers folks use over and over again....and then we would have thread where folks could discuss more technical details, post maps, etc. Just a thought!